Metallic burr or grinding-ring



I (No Model.)

B. TQTMAN.

- Metallic Burr'or Grindi ngRi ng.

No. 239,073. w Patented March 22,1881.

; 9. 'wwwm 800w $772 I 2 W I UNITED STATES PATENT OFFICE.

EDSELL TOTMA N, OF B ATAVIA, ILLINOIS.

METALLIC'BURR OR GRINDING-RING.

SPECIFICATION forming part of Letters Patent No. 239,073, dated March 22, 1881.

Application filed June 8, 1880.

being hadto the accompanying drawings and letters of reference marked thereon, forming a part of this specification of said invention, in which drawings- Figurel is a plan view of the workingface of the upper grinding-ring, the same showing a proper central" circular opening through which the grain to be ground or other sub stance is fed; and Fig. 2 is a like view of the lower grinding-rin g except its central aperture. Fig. 3 is a vertical central section of the two grindingrings when placed in juxtaposition for the practical operation of converting.

wheat into flour or for grinding other grain or substance. Fig. 4. is aview of a filling portion of the grinding-rings, which filling portion is interposed between the grinding-teeth of the grinding-rings. Fig. 5sh0ws a grinding-tooth having a sloping portion which is near the eye of the grinding-ring, and Fig. 6

a grinding-tooth having its working-face horizontal or on a uniform plane from end to end.

millstones are secured; second, to provide for adjusting the metallic edged blades or grinding-teeth and filling-pieces, and by their adjustment compensate for the wearing away of the workin g-faces of the grinding-teeth third, to provide for rendering a portion of the grinding blades or teeth self-sharpening by making them reversible end for end; and, fourth, to

(No model.)

provide ameans for clamping the grindingblades and filling portionsformingthe workingfaces of the grinding-rings within metal caps, whereby'they can be readily set in the caps or removed therefrom, as occasion may require, as well as adjusted.

The advantages of my improvements are great, since in ordinary burr-millstones as furrowed and dressed, if one portion of the Workin g-face wears away, the whole surface or working face is useless until the whole is re-dressed, whereas with my invention it is only necessaryto remove a worn or defective grinding tooth or blade and substitute a new one, or else regrind the worn or defective tooth and then reset it in proper grinding relation.

The advantage of my improvement is further seen as compared with a cast burr, since the latter becomes entirely useless when its working-face wears away a certain distance. Besides this it is impossible to cast a solid burr or grinding-ring with accuracy, since it will either spring in the casting or in molding, and in consequence will not grind even,whereas by my invention the adjustable grindingteeth can be made perfect, since the metal cap which holds them is turned true in a lathe, and then the teeth set in place therein, and all faced perfect in the lathe, the result being that grinding-rings so made will grind as fine and evenly as any burr-millstone.

The French \burr-millstone, as furnished by manufacturers, almost always is lacking in weight,'as well as out of balance, so far as the ing one of my grinding-rings may be made of metal and entire accuracy as to size and weight secured, such rings may be delivered to the miller in perfect condition for immediate use by the manufacturer.

In the drawings, A indicates the upper grinding-ring, and B the bed-ring, and in general construction and dress they are alike.

Their outer portions consist of a cast-metal cap or shell, 0, of circular form, with an outer rim, 0, and with a central annular portion, 0 which in the upper grinding-ring is the eye into which the grain or other substance to be ground is 'fed from the hopper. This cap is made of cast-iron, and is cast in one piece, and of any desired weight of metal. After having been cast, it is then placed in a lathe and both inside and outside turned down with exact uniformity, care being taken to have the inner face of the cap level. The cap is then pierced with screw-bolt holes to receive the screw-bolts, as shown in the figures, and is now ready to be supplied with its interior furnishing.

In the figures, 01 indicates a circular metal plate having its central portion cut out, so that the plate may be passed over the annular portion 0 and rest upon the inner level face of the cap, as shown, the width of this plate being a little less'than the distance between the parts a and c and so as to admit of a split or parted ring, 01, to be placed within the cap,as in Figs. 1, 2, and 3.

The dress of the grinding-ringis made up of grinding-teeth f and f and either soft-metal or wood filling-pieces g, the same being arranged to rest edgewise upon the circular plate 01 and extend from the inner surface of the split ring 01 to the annular portion 0 of the cap or shell 0, the whole being arranged togetherin respective relation, as signified clearly in Figs. 1 and 2. The grinding-teethfandf are made of hardened cast-steel, while the filling-pieces 9 may be made either of soft metal, such as iron, or of wood. The teeth f are of rectangular form, as seen in Fig. 6, their upper edges, as at e, from end to end, constituting their grinding-surfaces, which are level throughout, and which extend from the rim or annular portion 0 to the split ring 61. The teeth f are in general form rectangular, and like teeth f, but much thinner, and are made of plate metal, the same being hardened caststeel, as above stated. The working or grinding edges eof the teethf may be made sharpened, as signified in Fig. 5, or they may be' plane-surfaced, the same as teeth f. The teeth f are at their'inner ends made sloping, as at e, and thus,'in connection with the filling-pieces 9, form a proper passage for the substance bein g ground to pass outward toward the perimeter of the grinding-ring from the eye of said ring. .55

In practice the teeth fmay be made from two to two and a half or-even three inches in width, and have a grinding-face, as at e, of a 7 width equalto their thickness; and when, by

to correspond with the like slope on the teeth f. They are made longitudinally of wedge form, as clearly indicated in Figs. 1 and 2, and are located between the teeth f and between the teethfand f, as shown and when the interior furnishing of the cap 0 is first made up the top surface of these filling-pieces is made a proper distance below the grinding-surface or top edges of the teethfandf, in order to form the necessary feeding-drifts for the grain to pass from the eye of the grinding-ring along toward its perimeter, as well as to the grindin g-surfaces or grinding-edges of the teeth. Being made of soft metal or of wood, these filling-pieces are readily cut or filed away, as the case may be, when the grinding surfaces or edges of the teeth wear away so as to require the feeding-drifts to be deepened.

Having placed the ring-plate d in position, and also the split ring cl,'with the teeth and filling-pieces, as shown in Figs. 1 and 2, screwbolts, as at b I) I), equally spaced apart, are

now inserted through the screw-holes in the body portion of the cap 0, and so as to impinge against the ring-plate 61, while at the same time like bolts, as at b, are passed through the screw-holes in the rim 0, so that the inner ends of the bolts will impinge against the split ring d, as clearly indicated in Fig. 3. It will thus be seen that by screwing up the bolts 1) against the ring-plate cl the teeth f and f and filling-pieces 9 may be adjusted outwardly from the cap 0 as the grinding-faces of these teeth wear away, while also said teeth and filling-pieces may be held in any desired position to which the same may have been adjusted. The split or separated ring d (split or separated as at 00) allows said ring to be forced up against the outer ends of the teeth andfilling-pieces, and so hold them firmly in position when required, and by simply unscrewing the bolts b the teeth f and f can readily be removed for repair, or for the substitution of new teeth in their places, or for the purpose of turning or reversing the teeth f, end for end, and so-render them self-sharpening.

Instead of providing intermediate fillingpieces, g, the whole grinding-surface maybe formed of teeth having a beveled out upon their edges, so as to form feeding-drifts, as indicated in Fig. 7.

What I claim is- 1. A grinding burr or ring for'mills, comprising in its construction a disk having an inner and outer flange, a grindingsurface formed of separate blades or teeth which are movable together or separately independently of the disk, mechanism for adjusting the blades, and'mechanism for confining them in position when adjusted, and forreleasing them in order to allow for their adjustment, said confining and releasing mechanism also servingfiwhen desirable, for holding a major portion of the blades or teeth in position or together while a new blade is being inserted,

substantially as described.

IIO

2. A grinding burr or ring for mills, comdown independently of the disk, substantially 15 prising in its construction a disk having an as described. inner and outer flange, a grinding surface 4. The combination of the supporting and formed of grinding plates or teeth and fillingbinding rind,separate grindingplates or teeth,

5 pieces, the plates and filling-pieces being ada split ring and adjusting plate, and screws justable independently of the disk, mechanism for operating the split ring and adjusting- 20 for confining the plates and filling-pieces, and plate, substantially as and 'for the purpose demechanism for adjusting the plates and fillingscribed.

pieces together, substantially as described. Signed in presence of two subscribing wit- I0 3. The grinding rings or burrs of a mill, nesses.

comprising in their construction a disk, sepa EDSELL TOTMAN. rate movable blades which are reversible, Witnesses: means for confiningthe reversible blades, and CHARLES C. STEPHENS, means for adjusting the blades as they wear E. S.SMITH. 

